1. Field of the Invention
This disclosure relates to filled, flowable, light polymerizable polymeric compositions useful in restorative dentistry. Flowable, filled compositions can be used as crown and bridge materials either with or without alloy substrates; as reconstructive materials, filling materials, inlays, onlays, laminate veneers and the like, as luting agents or cements, and as orthodontic materials, sealants and the like.
2. Brief Description of the Related Art
In recent years, materials used for restorative dentistry have comprised principally acrylic resin systems, that is, acrylate or methacrylate polymers. Typical acrylate resinous materials are disclosed in U.S. Pat. No. 3,066,112 to Bowen, U.S. Pat. No. 3,179,623 to Bowen, U.S. Pat. No. 3,194,784 to Bowen, U.S. Pat. No. 3,751,399 to Lee et al. and U.S. Pat. No. 3,926,906 to Lee et al. Because acrylic resins alone are less than satisfactory, composite dental restorative materials containing resins and fillers were developed. The fillers are generally inorganic materials based on silica, silicate based glasses, or quartz.
Over the years, there have been a number of refinements in the matrix resins, fillers and other additives such as antioxidants, ultraviolet absorbers, polymerization initiators, polymerization accelerators, and the like, used in dental restorative materials. There are now available materials which exhibit high diametral tensile strength, excellent optical properties and polishability, and low water absorption while, at the same time, complying with all of the requirements specified in the American Dental Association (ADA) Specification No. 27 for direct filling resins. Particularly suitable dental restorative materials are compositions having improved inorganic filler materials such as those described in U.S. Pat. Nos. 4,547,531 and 4,544,359, disclosing visible light polymerizable compositions.
Despite recent advances in the development of filled dental restorative materials there remain opportunities for improvement in the flexural strength of composites used as crown and bridge materials, denture base materials, luting agents or cements, orthodontic appliance materials and sealants. In particular, improving the handling characteristics of dental restorative materials that facilitates ease of application is highly desirable.
A dental restorative composition comprises about 35 to about 43 wt %, based on the total dental restorative composition, of a polymerizable, ethylenically unsaturated resin composition, wherein the resin composition comprises, based on the resin composition alone, about 25 to about 35 wt % PCDMA, about 40 to about 50 wt % EBP-DMA, about 18 to about 28 wt % Bis-GMA, and about 55 to about 70 wt %, based on the total dental restorative composition, of a filler system, wherein the filler system comprises a silanized barium glass containing about 20 to about 60 wt % barium oxide based on the weight of silanized barium glass.